High-resolution oxygen-17 NMR spectroscopy of solids by multiple-quantum magic-angle-spinning
نویسندگان
چکیده
High-resolution solid state nTo NMR spectra of nTo-enficbed compounds were observed with multiple-quantum magic-angle-spinning (MQMAS) experiments. The resolution of the 170 MQMAS spectra is approximately 30to 150-fold higher than that found in conventional 170 MAS spectra, making it possible to detect crystallographically distinct oxygen sites. It is shown that into MQMAS studies are feasible for systems with 170 quadrupole coupling constants up to 7 MHz, provided that sufficiently high radio-frequency field strengths (> 120 kHz) and spinning speeds (~ 20 kHz) can be achieved. © 1997 Published by Elsevier Science B.V.
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